In the study that follows, I argue that Mary Shelley enters into the lively debates on botany and female sexuality which were prominent in her literary and cultural milieu through her engagement with what I call the ‘botanical woman’ figure in her novels Mathilda and The Last Man. Following suit from the botanical texts of authors such as Carl Linnaeus, Erasmus Darwin, and especially Mary Wollstonecraft, Shelley interrogates questions about female sexuality, the role and education of women in society, and marriage through the depiction of women as sexualized plants and their relationships with men. Through these botanical women, I suggest that Mary Shelley shows how women, when rendered flowers subject to male desire, fail to cultivate their rational minds or to reach their full potential. While men are educated and cultivated to grow their minds, write books, lead leagues of men in politics, women are reared to be decorative or ornamental to men’s lives, playing the role of wife or mother. Mathilda dies purposeless, a failed wife, mother, and author, her rational potential wasted. Shelley shows that even for those exceptional few, like Perdita, whose minds and political talents find a way to grow despite all obstacle, the patriarchal system would find a way to diminish them to the same fates as women like Idris whose only ambitions are to be wives or mothers; to die, like flowers in decay.